Health Blog

(CNN) Varicose veins may be an early warning sign of potentially deadly blood clots, suggests a study published Tuesday in the journal JAMA.

Enlarged and gnarled varicose veins and deep venous thrombosis, a clot that forms in the deep veins of the body, are strongly associated, the Taiwanese researchers found.

Though they looked at the health records of more than 425,000 adults, the researchers say that even more work is needed to understand whether this relationship is one in which varicose veins directly cause blood clots or whether the two conditions simply have a similar origin.

“The most common question from a varicose vein patient in the vein clinic is: ‘Will varicose vein bring any health risk for me?’ ” said Dr. Shyueluen Chang, first author of the study and a phlebologist and dermatologist at Chang Gung Memorial Hospital in Taoyuan, Taiwan.

For this reason, Chang said, learning about potential relationships between “varicose veins and health-threatening diseases is important.”